A Physician's Guide to the Use of Gene Expression Profile Ancillary Diagnostic Testing for Cutaneous Melanocytic Neoplasms.

Objectives: Some melanocytic neoplasms suspicious for melanoma require additional workup to arrive at a final diagnosis. Within the last eight years, gene expression profiling (GEP) has become an important ancillary tool to aid in the diagnosis of melanocytic neoplasms with uncertain malignant potential. As the usage of two commercially available tests (23-GEP and 35-GEP) evolves, it is important to answer key questions about optimal utilization and their impact on patient care. Methods: Recent and relevant articles answering the following questions were included in the review. First, how do dermatopathologists synthesize the available literature, the latest guidelines, and their clinical experience to determine which cases would be most likely to benefit from GEP testing? Second, how best can a dermatologist convey to their dermatopathologist that the use of GEP in the diagnostic process could provide a more clearly defined result and thereby help empower the dermatologist to provide higher-quality patient care when making specific patient management decisions for otherwise pathologically ambiguous lesions? Results: When interpreted in the context of the clinical, pathologic, and laboratory information, GEP results can facilitate the rendering of timely, accurate, and definitive diagnoses for melanocytic lesions with otherwise uncertain malignant potential to inform personalized treatment and management plans. Limitations: This was a narrative review focused on clinical use of GEP compared to other ancillary diagnostic tests performed postbiopsy. Conclusion: Open communication between dermatopathologists and dermatologists, especially regarding GEP testing, can be a vital component to achieve appropriate clinicopathologic correlation for otherwise ambiguous melanocytic lesions.